[unreadable] This application describes a five-year integrated program of research and training, including a qualitative study examining the use of club drugs among men who have sex with men (MSM). Club drugs are synthetic compounds with stimulant and hallucinogenic properties, such as methamphetamine (crystal meth), 3-4 methylenedioxymethamphetamine (MDMA, or Ecstasy), ketamine (Special K), gamma hydroxybutyrate (GHB), and volatile nitrites (poppers). Use of club drugs has grown substantially in the last decade among MSM in the gay party circuit, bathhouses, and clubs, and has been associated with increased sexual risk-taking. [unreadable] [unreadable] There are two phases of this qualitative study. The aims of Phase I are to describe the culture of club drug use, to delineate the socialization process into club drug use, and to examine the relationship between club drug use and risky sexual behavior among MSM in Washington, DC. Phase II builds on knowledge obtained in Phase I and further explores these aims, but addresses them specifically among Latino MSM in two cities: Washington. DC and Miami. The study employs qualitative research methods, which are particularly suitable to study hidden populations and to explicate complexities of behavioral patterns. The multiple approaches of ethnographic observations, key informant interviews (4 in Phase I and 8 in Phase II), focus groups (4 groups of 10 participants in each phase), and in-depth individual interviews (10 participants in Phase I and 30 participants in Phase II) will provide different perspectives and knowledge, and thus enable a rich depiction of club drug use and sexual risk. [unreadable] [unreadable] The study will be conducted under the mentorship of senior researchers in the field. In addition to interaction with mentors, training activities will include directed reading, post-graduate classes, and research team meetings and presentations. The objectives of the training component are for the applicant to develop expertise in methods and data analytic approaches for qualitative research; to develop expertise in the current literature on drug use, and specifically club drug use, in the MSM community; and to develop greater awareness of the responsible conduct of this type of research. Moreover, the ultimate objectives are to develop of a theoretical model concerning club drug use and sexual risk, and to establish an independent program of research concerning these behaviors with particular emphasis on Latino MSM. [unreadable] [unreadable] [unreadable] [unreadable]